Added support for bundles without a vendor name e.g. AppBundle from Symfony best practices

hmm, I find this one pretty strange. Why do you include `Bundle\` in the optional part?

The only thing you should make optional is the vendor, so `[A-Za-z0-9]*\\\`. To do this, something like `@(?:([A-Za-z0-9]*)\\\)?(Bundle\\\)?` is better.